Delete a scipt that autoloads that was run
Afaik you cannot delete the script from the outside, but you CAN disable its execution temporarily so you can get instide the blend file. Run blender from the system command line with the disable autoexec flag, like this:
blender —disable-autoexec

…and then open your file with that instance of Blender.
PS: note that if blender has not been added to PATH on Windows, this will not work directly. First, either navigate with Windows Explorer to blender’s program files and open the command line there, or just open the command line and navigate to the directory first:
cd C:\Program Files\Blender Foundation\Blender

.\blender —disable-autoexec

The .\ on the blender line is necessary in PowerShell.
Of course, you can also just add blender to PATH, but that’s an OS-specific question.